Cardiac Codex

Transition Zone

A Cardiac Rhythm Management term on the RCES exam blueprint, defined for cath lab and EP clinicians.

The temporal window during entrainment pacing of a tachycardia in which surface ECG morphology progressively shifts from intrinsic tachycardia morphology to a purely paced morphology; atrial activation patterns observed during this window help distinguish accessory pathway conduction from AV nodal conduction.

Domain: Cardiac Rhythm Management · Blueprint: RCES exam guide

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